Hi there, I don't know if your experience will be the same but thought maybe if I told you what happened when I went it might be of some use?
I too was suffering from severe depression, got referred to community mental health team and for appointment with psychiatrist.
On the day of the appointment I first met with a mental health nurse who was part of community mental health team.
We talked for about 40mins to an hour while she took a history from me regarding how I'd been feeling, for how long, any significant events. All of the things you'd expect to be asked by your GP really.
It was all done in an environment they'd obviously tried to make look homely and comfortable; offering cups of tea and the like as if you're just having a chat with your friend.
The nurse then fed back the information i had given her to the psychiatrist.
Then I met with the psychiatrist and he talked more about some things he wanted more information on, and the nurse stayed with me the whole time.
The psychiatrist gave me my diagnosis, suggested a few new medications to try that my GP hadn't thought of yet, then wrote to my GP with his assessment.
All in all it was pretty much what you'd expect, if you've ever had any kind of appointment in counselling or CBT or psychology or anything like that then most introductory appointments are quite similar.
Basically you just outline your problems in your own words to them. The appointment I had certainly wasn't intimidating at all and they'd obviously gone to great lengths to make this the case.
I hope this is of some help, if you've got any more questions feel free to ask.
I'd definitely go to the appointment though, it could end up being really beneficial to you.
X